1. Field of the Invention
The present invention relates generally to heat exchangers for motor vehicles and, more specifically, to a high performance louvered fin for a heat exchanger in a motor vehicle.
2. Description of the Related Art
It is known to provide a louvered fin for a heat exchanger such as an evaporator in a motor vehicle. An example of such a louvered fin is disclosed in U.S. Pat. No. 5,738,168. The louvered fin typically is a corrugated fin having generally planar walls joined in a "V" shape at crests. The louvered fin also has a plurality of louvers bent integrally out of the walls at an angle for the purpose of breaking up airflow over the fins and increasing heat transfer. Further, the louvered fin may have multiple louvers in which the louvers are divided into a pattern of alternating, adjacent sets of louvers to guide airflow in an attempt to induce turbulent flow therein. Commonly, two sets of louvers are used, an entrance set and an exit set separated from one another by a central portion. When air flows over the walls of the louvered fin, the airflow will engage the louvers of the entrance set and be deflected upwardly through the wall at the angle of the entrance set of louvers. Air in the deflected stream flows between a pair of adjacent central portions in two adjacent walls. The air is deflected back through the louvers of the exit set in the same way. It should be appreciated that the airflow has a generally shallow bell curve shape.
Another known louvered fin for a heat exchanger such as an evaporator is disclosed in U.S. Pat. No. 4,580,624. In this patent, groups of louvers are sloped alternately or in different combinations on the fin.
Other examples of known fins for heat exchangers are disclosed in U.S. Pat. No. 3,214,954 and Japanese Patent No. 10-141805. U.S. Pat. No. 3,214,954 discloses a fin roll and Japanese Patent No. 10-141805 discloses a multi-stage fin.
Although the above fins have worked for a heat exchanger, it is desirable to provide a corrugated fin that allows louvers to direct air through the heat exchanger core with minimum turning while maximizing the number of louvers within the airstream for increased heat transfer. It is also desirable to provide a split louver that allows each section of the louver to maintain and direct airflow in a single direction for a minimum drop in airside pressure for increased heat transfer. Therefore, there is a need in the art to provide a louvered fin for a heat exchanger that outperforms conventional louvered fins in both heat transfer and air pressure drop.